CHANGELOG.md in glimmer-2.3.0 vs CHANGELOG.md in glimmer-2.4.0

@@ -1,9 +1,16 @@
 # Change Log
 
 Related Change Logs:
 - [glimmer-dsl-swt/CHANGELOG.md](https://github.com/AndyObtiva/glimmer-dsl-swt/blob/master/CHANGELOG.md)
 
+### 2.4.0
+
+- Support passing arbitrary options to `Observer` `#observe` (`#register`) method (not just properties, like `recursive: true` for example)
+- Make observing nested arrays within an array optional with `recursive: true` option
+- Make `Observer` `dependents` collection rely on Concurrent::Hash when available
+- Fix `Observer` cleanup of registrations and dependents on `#deregister` (was not cleaning up everything because observables were changing `#hash` value on content change and slipping through the cracks as a result)
+
 ### 2.3.0
 
 - Have observing `ObservableArray` automatically notice if any values are nested arrays and observe them for micro-changes (recursively all the way down)
 
 ### 2.2.2